Show cover of HVAC School - For Techs, By Techs

HVAC School - For Techs, By Techs

HVAC School is the ever growing online source for real training topics for technicians in the Air-conditioning, Heating and Ventilation Fields. In the podcast, we will share recorded training, tech ride alongs, share challenging diagnostic scenarios. All to help make the industry, your company, and your truck a better place to be.

Tracks

HVAC Performance Summit w/ Dominick G.
Dominick Guarino from NCI joins the podcast to talk about the High-Performance HVAC Summit, an upcoming event hosted by NCI from April 17–20. The National Comfort Institute (NCI) is a training organization that helps technicians learn crucial skills and succeed through high-performance contracting. High-performance contracting is based on the mindset of “don’t just promise performance; prove it.” To maximize technicians’ potential, NCI teaches technicians how to test equipment properly and monetize their skills. Techs can then use their knowledge to teach the homeowner about the system and solve problems with sales; they can earn money while being solutions-oriented. NCI’s High-Performance HVAC Summit is a training event geared toward HVAC business owners and contractors. It started as a membership conference for education and networking, and it has since expanded to include like-minded HVAC professionals from all walks of life. Workshops are led by a mix of contractors and NCI staff, and there are breakout sessions and other various session types.  This year’s High-Performance Summit theme will be “It All Starts With Service.” The four focal points of the workshops will be lead generation through service and maintenance, CO safety, the lead handoff from service to sales, and maintenance agreements. One more session will focus on hands-on testing, called “Low-Performance Town” this year, and there will be a panel about the future of high-performance HVAC. Dominick and Bryan also discuss: Dominick and NCI’s history in the industry High-performance maintenance Consumers who do their research The HVACR Training Symposium High-Performance Summit Awards Banquet NCI’s collaboration with other industry leaders and organizations   Visit https://www.gotosummit.com/ to learn more about the High-Performance Summit. If you decide to register for the summit, type HVACSCHOOL in the coupon code section for a $100 discount. Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
45:40 3/23/23
Training, Combustion and More w/ Tony G.
In this podcast from AHR 2023, Tony Gonzalez from Fieldpiece joins Bryan to talk about training, combustion, and more. Fieldpiece has a new combustion analyzer that reduces the cost of tool ownership and maximizes the tool's uptime, namely by using a long-lasting sensor. The combustion analyzer's oxygen and CO sensors seal up when the combustion analyzer is turned off, which pauses degradation. The sensors are also field-replaceable and come with a 4-year warranty. The CAT85 also has a built-in dual-port manometer (which can measure static pressure) and can measure a live draft pressure during combustion analysis. Some common misconceptions exist around combustion analyzer sensor lifespans and calibration. The sensor life refers to how long a sensor can output a signal to generate a reading; it doesn't refer to the accuracy of the sensor at the end of its life. Calibration keeps the sensors accurate, especially because sensor accuracy tends to degrade over time. To get the most out of your sensor, yearly calibration is recommended. Fieldpiece is also launching its ambassador program, which is a network of independent trainers with field knowledge who have been trained to become Fieldpiece product experts. Those ambassadors then train contractors and technicians on behalf of Fieldpiece. Tony and Bryan also discuss: Fieldpiece's sensor calibration process Water freezing in combustion analyzer traps Distinguishing your company from the competition with superior tools Technical training from Fieldpiece Fieldpiece leak detectors and new A2L refrigerants Infrared vs. heated diode leak detector sensors   Learn more about Fieldpiece tools at https://www.fieldpiece.com/ or ask about training by emailing training@fieldpiece.com.  Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
22:54 3/14/23
The Future of Refrigerants is Here With Opteon XL41
In this podcast from AHR 2023, Brandon Marshall from Chemours and Chris Forth from JCI talk about the future of refrigerants and Opteon XL41 (R-454B). Refrigerant regulations are changing to pave the way for lower-GWP refrigerants, but M1 is also in full swing. M1 refers to the U.S. Department of Energy's implementation of the new efficiency standards for A/C units and heat pumps (SEER2, EER2, etc.). These standards changed the equipment testing procedure to match field conditions more closely. Opteon is the next-generation portfolio of low-GWP refrigerants for Chemours as a successor to the legacy refrigerants in the Freon product line. These refrigerants are a response to the HFC phasedown outlined in the AIM Act. JCI chose to use Opteon XL41, an HFO, for its equipment due to Opteon XL41's low GWP compared to R-32 and because of the similar operating pressures and temperatures to R-410A. A2Ls are a permanent change in the industry, and their safety considerations and best practices are here to stay. However, even though A2Ls are more flammable than A1 refrigerants, they are nowhere near as flammable as A3 refrigerants. Just about any refrigerant can propagate flame under the right conditions (including A1s), so A2Ls are only a little bit more flammable than those. Brandon, Chris, and Bryan also discuss: Brandon and Chris's industry experience The transition from CFCs to HCFCs to HFCs Refrigerant reclamation Upcoming GWP limits  Hydrofluoroolefins (HFOs) A2L refrigerant product testing Staying up to date on A2L training resources Some of the prominent flammable refrigerant trainers Smuggled and counterfeit refrigerants   Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
34:23 3/9/23
MeasureQuick is EXPLODING with Jim & Joe
In this podcast from AHR 2023, Jim Bergmann and Joe Medosch talk about measureQuick and the ways it's EXPLODING with growth and new features. They also talk about heat pumps, electrification, and other hot topics in the industry. Jim Bergmann recently released an open letter about heat pumps on LinkedIn; he addressed the shortcomings of the industry from a skill standpoint. The lack of training and standards may be mitigated with proper training (and an understanding of building science fundamentals) or by embracing hybrid systems. Heat pumps may also perform relatively poorly during extreme weather events and may not manage temperature swings well. MeasureQuick has recently been working with ACCA and formed other partnerships to allow for standardization (for companies and the industry as a whole). More companies are also integrating with measureQuick, especially TEC and their TrueFlow Grid; accuracy across brands tends to be pretty consistent, and measureQuick allows you to mix and match tools. The customer-facing side of measureQuick has also received some development, which allows the customer to see the value and quality of their installation. MeasureQuick is keeping up with the growing pains by doing constant testing. Joe and Jim make sure the user experience is seamless, intuitive, and free of problems or inconveniences. Jim, Joe, and Bryan also discuss: Fixing the building envelope Heat pump vs. gas furnace comfort Energy Star certification for installations measureQuick user base milestones Industry leaders, supporters, and partnerships New measureQuick workflows Joe Medosch's role at measureQuick The challenges of the HVAC trade Technology challenges for measureQuick's users Free and paid measureQuick features   Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
35:06 3/7/23
Infiltration Skeletons Behind Closed Doors w/ Genry
Genry Garcia returns to the podcast to talk about pressures in the building envelope, namely the infiltration skeletons behind closed doors. When doing load calculations (Manual J), we need to know how much of the heat load, especially the latent heat load, comes from leakage in the building envelope and the ducts. Opening/closing doors and windows can also worsen the issues that stem from infiltration due to upsetting the balance of pressures in the home. Smoke pencils and other similar tools can give you an idea of the pressure in a home and how it could change when doors open or close. Since there is a lot of room for inaccuracy in extreme climates (especially those with high latent loads), many HVAC systems are oversized and underperform. Some building design features also exacerbate problems presented by oversized HVAC systems. To get the data we need to design systems that mitigate those issues, we need to do a blower door test. Downsizing the tonnage in retrofits or replacements usually has advantages, but it must be done right, and customers may not always want to do that. It's the contractor's responsibility to give them a choice and educate them about the options and what the thorough diagnostic process looks like, including balancing the home and checking the pressure in relation to the outdoors. Genry and Bryan also discuss: Positive and negative pressure in certain rooms Exhaust ventilation and pressurization Using See Stack to see differences in loads Leaving the fan in the "on" position Useful tools Variables in lab-based testing and field testing Getting hung up on the 3 Pascals rule of thumb Leaky rooms vs. whole-home leakage   Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
47:41 3/2/23
Understanding Leak Detectors With Inficon
In this episode recorded live at AHR Expo 2023, Nick from INFICON joins Bryan to talk about leak detectors and how we can improve our understanding of them. Some leak detectors, including the INFICON Stratus, measure concentrations in PPM (parts per million). When measuring PPM, we have to keep in mind that it doesn't indicate the size of the leak or leak rate, but it does help us pinpoint the leak location. In some cases, we also have to watch for automatic zeroing capabilities. Leak detectors come in many varieties, including heated-diode, ultrasonic, and infrared; each type has unique maintenance needs. Heated-diode leak detectors are sensitive, but their sensors wear off with frequent use and will require replacement. Infrared leak detectors use infrared absorption and don't degrade over time the way heated-diode leak detectors do. An ultrasonic leak detector picks up the sound of refrigerant and air leaking out of a hole to pinpoint the leak. It's a good idea to approach leak detection with a plan, including starting high on the coil and moving down (because refrigerant is heavier than air and may set off the leak detector below the actual leak). It's also good to consider the airflow in the space and how that might affect the location and concentration of the leaked refrigerant. Nick and Bryan also discuss: Pressure, hole shape, and leak rate Understanding tool maintenance Infrared leak detector usage and considerations Common causes of leak detector failure D-TEK product line CO2 and hydrocarbon sensors for leak detectors D-TEK Stratus modes (cloud hunting and pinpoint) Applications for D-TEK Stratus leak detectors "False" positives   Learn more about INFICON at https://www.inficon.com/.  Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
30:25 2/28/23
Making Cold Climate Heat Pumps Work w/ Copeland and White Rodgers
In this episode recorded live at AHR Expo 2023, Dustin and Jim from Copeland/White-Rodgers join Bryan to talk about the use of heat pumps in cold climates. They talk about the history of heat pump innovation and talk about changes to come. Variable-speed and two-stage compressors, as well as advanced controls, make it easier for contractors to control sizing and for heat pumps to perform to acceptable standards in cooler climates. Contractors in cold climates also rely on dual-fuel models that use electric and gas heat, which makes it easier for the system to move the desired amount of heat. Variable-speed and two-stage compressors help the system deal with different heating and cooling capacities; in cooling mode, these technologies can also help with latent removal if the blower is also able to vary with the compressor.  Advanced controls, especially universal controls, also help with defrost management, a key component of heat pump performance. When defrost is managed effectively, customers can yield energy savings. The White-Rodgers universal defrost control comes with coil and outdoor temperature sensors (thermistors) to determine when the unit is ice-bound; it also has a thermostat that can control second-stage heat. Dustin, Jim, and Bryan also discuss: Electrification and heat pump sales Vapor injection and compression ratio control Freq drives White-Rodgers universality and nomenclature Timed vs. demand defrost Electric heat vs. gas/oil heat costs WR Mobile app Multi-volt contactors (White-Rodgers SureSwitch) Pool heat pumps and contactors Crankcase heaters, long line sets, and total system charge A2L refrigerant testing   Learn more about White-Rodgers products on the WR Mobile app, our partner page at https://hvacrschool.com/partner/emerson-white-rodgers/, or the website at https://climate.emerson.com/en-us/brands/white-rodgers.   Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
46:57 2/23/23
RTU Retrofits Facts and Considerations with JCI
In this episode recorded live at AHR Expo 2023, Matthew Schlegel, the Commercial Product Manager of Ducted Systems from JCI (Johnson Controls) joins Bryan to talk about rooftop unit (RTU) retrofit facts and considerations. When doing an RTU retrofit, you want to make sure you know the budget before anything else; larger budgets will allow you to implement things like VFDs and even VAV technology. In many cases, you may consider adding an economizer for "free" cooling and energy savings. You also want to know what you will get out of a retrofit in terms of value, especially when it comes to system efficiency and longevity. Some common IAQ upgrades for RTUs include improved filtration, especially with MERV 13 filters. Economizers also allow you to control the amount of outside air with the help of an exhaust system or even barometric relief. UV lighting can also be used in light commercial RTUs. When doing a retrofit, you'll want to pay attention to the existing equipment's footprint. Sticking to that footprint will make the replacement aspect easier. The utility and electrical infrastructure are also important to consider, as you won't want to replace the existing piping, wiring, and connections.   With regulations and technology constantly changing, it helps to be able to contact the manufacturer to assist with the retrofit process. Companies like JCI are trying to assist contractors with installations by providing guidance and education in the field. Matthew and Bryan also discuss: Matthew's professional experience at JCI Adding economizers and VFDs Convertible filter racks Cost-benefit analysis resources Changing regulations Interfacing with the manufacturer during the retrofitting process   To learn more about JCI, visit https://www.johnsoncontrols.com/. Learn more about the HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
20:25 2/21/23
Troubleshooting The Modern ECM
Chris Mohalley returns to the podcast to talk about troubleshooting the modern ECM (or EC motor) and give diagnostic tips. ECMs are electronically commutated motors; they are mechanical motors with an electronic control module that dictates everything the motor does. As with all motors, ECMs have inputs and outputs. If the motor is not running, the first step is to check the line voltage and make sure that it is correct and connected continuously, as that's one of the main inputs on all ECMs; there is no relay or switch on the line side. The motor itself is the output, so you will know if the output is correct if the motor is rotating and generating airflow as intended. Constant-speed and constant-torque motors can all be diagnosed with a basic voltmeter. One of the most difficult parts of troubleshooting constant-torque ECMs is knowing how the taps are programmed by the manufacturer; reading the manual and schematic is advantageous during diagnosis, especially as these motors have evolved to use pulse-width modulation (PWM) and have nine speeds instead of five (energizing pin 1 at the same time as another pin, diagnosed with 24v AC). Constant-airflow motors tend to have inputs that are less complicated than the five or nine-speed taps. Chris and Bryan also discuss: Inputs: line voltage and signals TechMate Pro, multimeters, and Genteq TECINspect diagnostic tools Constant-speed vs. constant-torque vs. constant-airflow motors Diagnosing PWM signals with DC voltage Adjusting airflow with DIP switches Are board and motor failures common? Why we don't diagnose the motor separately from the control   Learn more about Regal Rexnord's FREE training at https://regal.mmu.com. Learn more about the HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
31:10 2/16/23
Training for the Future w/ Clifton & ESCO
Clifton Beck of ESCO Group returns to the podcast to talk about training for the future. He also talks about how he became an educator, what it's like to be a trades educator with ESCO Group, and how educators can handle the recent HFC phasedown and the rise of A2L refrigerants. Especially with the COVID-19 pandemic, mass media has changed the way the industry thinks about training. Organizations like ESCO have evolved, and that is evident in their curricula; changes are being made to keep up with field tools and equipment to make sure technicians are up to date. A large network of industry experts makes these training curricula possible. Virtual and media education have changed the way we think of educators. Many of the most knowledgeable people in the industry, including people like Craig Migliaccio, work in the field and aren't traditional educators but have a large positive influence on the industry due to social media. Refrigerant regulation changes, including the HFC phasedown, present opportunities for training to focus on combating misinformation and adapting to field conditions. Training should aim to eliminate confusion and anger in these situations. Proper installation and service procedures will make the A2L transition much easier. Clifton and Bryan also discuss: Clifton's professional history HVAC experts and relationship building ESCO Institute and HVAC Excellence The evolution of educators and expectations for them HFC phasedown facts Recovery, recycling, and reclaiming refrigerant appropriately Commercial vs. residential HVAC/R and refrigerant regulations Educators as social media personalities HVAC Excellence Conference   Learn more about ESCO Group's resources at https://www.escogroup.org/. You can also check out the ESCO Group YouTube channel at https://www.youtube.com/@escogroup. Learn more about the HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
40:31 2/9/23
MERV vs. Motors
ECM expert Chris Mohalley joins the podcast to talk about the balance between selecting air filtration and motor performance, also known as "MERV vs. Motors." As the industry realizes that filtration is more important, we're starting to see an interest in filters with MERV ratings of 13 or higher. However, there are some design challenges associated with static pressure drops across filters, motor responses to static pressure, and airflow. If the airflow isn't set properly, that could affect the refrigerant charge and temperature rise. PSC motors' performance directly follows the load; as static pressure increases, the airflow rate produced by the motor decreases. They may also make loud noises when the static pressure is high but satisfactory airflow. However, they are robust and don't typically fail quickly due to high static pressure. Electrically commutated motors (ECMs) are operated by electronic controls and come in constant torque or constant airflow varieties. The former has a performance curve (like a PSC motor) but doesn't appear to suffer from longevity issues when the static pressure is high; the latter can adjust airflow based on static pressure, but it is likely to have issues maintaining airflow during high static pressure conditions. Regardless, there is still an operational envelope; going outside of that envelope will likely result in a capacity and/or efficiency hit if there is high static pressure. Chris and Bryan also discuss: COVID-19 pandemic and the evolution of filtration Face velocity across filters Amps in constant torque vs constant airflow motors Swings in airflow/performance Educating the customer about "upgrading" filters Using performance manuals   Learn more about Regal Rexnord's training at https://regal.mmu.com. Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
39:28 2/7/23
Effective Filtration & More w/ John Ellis
John Ellis, a business consultant who specializes in IAQ training, joins the podcast to talk about effective filtration, product development, and more. John has recently worked with an OEM to bring field practicality and application to the engineers who design products. Filtration design is a relatively poorly understood concept in the industry; we tend to overlook a filter's ability to remove particulates from the air when we prioritize static pressure drop. We have to understand how the duct design can make higher-MERV filters work and how the face velocity plays into design and comfort. John also talks about bypass HEPA filtration and its appropriate uses and potential for misapplication. Bypass HEPA may be integrated with the HVAC system (but run independently of the system) or installed independently of the HVAC; its effectiveness will be dictated by its runtime, and it doesn't filter everything.  IAQ products and strategies need to produce quantifiable results, and our industry needs people to be trained to measure and produce those results, not push products. Education, integrity, and competence are the keys to starting conversations about IAQ methodologies that actually benefit the customer. When we're ready to have those conversations with the customer, we can show the customer that we prioritize their health, safety, and comfort; it's good to use maintenance procedures as times to follow up with the customer and make sure their IAQ needs are being met. Communication is critical here. John and Bryan also discuss: Design, production, and distribution MERV ratings Oversized filter-back returns with media filters Blow-by  Charcoal carbon pellets vs. activated carbon Oxidizers and microbiology disruption Sales resistance & being pushed to make more sales Problems with circuit boards   Learn more about John's work at https://thenewflatrate.com/ or contact him directly at (505)-652-8119. Learn more about the 4th Annual HVACR Training Symposium or buy a virtual ticket today at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
50:12 2/2/23
Do Houses Need to Breathe? w/ Allison Bailes
Dr. Allison Bailes from Energy Vanguard joins the podcast to answer the age-old question: do houses need to breathe? He also talks about his new book, A House Needs to Breathe... Or Does It? You can purchase that book directly through the Energy Vanguard site at https://energyvanguardstore.com/ or on Amazon. HVAC professionals can benefit from learning about building science because there is a lot of overlap between the two, and an HVAC technician who knows about building science can set themselves apart in the market. In short, Dr. Bailes doesn't think a house needs to "breathe," especially if a house brings in low-quality air, especially humid air, through gaps and cracks. Some people also use the term "breathe" differently; some may be referring to leakiness, and others may refer to drying out a house. It is necessary for a house to be dry, but we want to make sure that fresh air is controlled. If you build a home tightly, you have to ventilate it correctly. We have to control air, liquid water, water vapor, and heat. Heat is especially complicated, as it has three different ways of moving and can come in sensitive and latent varieties. One way of controlling those is through control layers like vapor barriers, though these aren't always needed; we must understand the vapor flow to determine if a vapor barrier is necessary. Dr. Bailes and Bryan also discuss: Energy Vanguard's resources The chapters of "A House Needs to Breathe... Or Does It?" IAQ - filtration, humidity control, ventilation, and source control Challenges with attic air Dr. Bailes's book-writing process The HVACR Training Symposium and other events w/ Dr. Bailes   Keep up with Energy Vanguard, read the blog, and subscribe to the weekly newsletter at https://www.energyvanguard.com/. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
31:36 1/26/23
What the Heck is High Performance HVAC w/ David Holt
David Holt with the National Comfort Institute (NCI) returns to the podcast to talk about high-performance HVAC and what the heck it even is.  High-performance HVAC is all about delivering the highest possible equipment performance out of the box. High-performance HVAC is a key element of NCI's work; equipment should be able to deliver the health, comfort, safety, reliability, and efficiency expected by the occupants, and equipment that can't do that often has root issues we need to troubleshoot and fix. In many cases, the root cause has something to do with airflow issues. As contractors, we can focus more heavily on testing fan airflow to get to the bottom of poor HVAC performance, even when there may not be an apparent airflow problem. We need the proper test instrumentation to measure CFM, a key indicator of performance. We can't expect to maximize system performance until the airflow is correct across the heat exchange surfaces. Many factors that contribute to poor equipment performance actually have to do with building science, including issues like air leakage. Although HVAC contractors can't control that, we can be successful if we have a culture and mindset that makes us put our customers first and work with the circumstances we're given to deliver the best possible solution. David and Bryan also discuss: David's role at NCI Manufacturer, distributor, contractor, technician, and customer relationships How to measure CFM effectively Effects of improperly  Issues that arise during building construction Parts vs. equipment vs. systems What makes a good service technician The high-performance mindset Having a classroom vs. a commitment to training   If you want to get more involved in HVAC training, you can text David at (706)-332-2212 or visit https://nationalcomfortinstitute.com/pro/. Learn more about NCI's High-Performance HVAC Summit at https://www.gotosummit.com/.  Check out the HVACR Training Symposium and order your virtual tickets before, during, or after the symposium (Jan 19-21, 2023) at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
46:32 1/19/23
Setting Realistic Customer Expectations w/ Ed Janowiak
Ed Janowiak returns to the podcast to talk about setting realistic customer expectations when designing residential HVAC systems across climates, seasons, and load conditions. Being honest and aggressive is one of the best ways to set realistic expectations, and our load calculations and equipment selection need to reflect that. Manual J calculations must consider non-design days, not just the design conditions, including partial load conditions. Partial load conditions that aren't accounted for may make it more difficult for the HVAC system to control latent heat, potentially leading to moisture problems indoors. We have to set expectations in the summer a bit differently than we set expectations in the winter, and we must account for the equipment type when we create expectations. Heat pumps perform differently than furnaces, and oversized furnaces typically present fewer problems than oversized heat pumps in areas with high latent loads.  Clients must also be willing to acknowledge that systems won't perform exactly as designed during partial load conditions. You can put the information in writing and make clients sign the paperwork to ensure that they understand the expectations you've set. Laying out expectations and making clients read them is a good way to prevent conflict or identify clients that may not accept the expectations. Ed and Bryan also discuss: Ed's three "Hate Me" reasons Oversizing furnaces vs. straight-cool A/C units vs. heat pumps Electrification Heat pumps in cold climates Humid vs. arid climates Designing systems with ancillary dehumidification Not being responsible for clients' lifestyle choices ACCA collaboration and industry support   Learn more about the training ACCA has to offer at https://www.acca.org. Check out the HVACR Training Symposium and order your virtual tickets before, during, or after the symposium (Jan 19-21, 2023) at https://hvacrschool.com/symposium.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
45:43 1/12/23
Mini Split Install and Service Tips
Craig Migliaccio, aka AC Service Tech, returns to the podcast to share his knowledge about mini-split install & service. He also talks a bit about his upcoming book, “Inverter Mini-Split Operation and Service Procedures.” Mini-splits are unique because they are compartmentalized in ways that traditional central-air ducted systems are not. Mini-splits come in many varieties, including ducted and ductless types, as well as multi-zone types. Many are inverter-driven and have more electrical efficiency as a result and can vary their capacities based on load variation.  Mini-splits have metering devices at their outdoor units, and these devices may be electric expansion valves (EEVs) or capillary tubes. Inverter mini-splits also don’t have filter driers because their PVE oil doesn’t have the same acid concerns as POE oil, and they don’t have traditional liquid lines. Flare connections are also critical when installing ductless systems, especially because you want systems to be tight to prevent leaking and contamination. Craig likes eccentric flaring tools with offset cones, and he recommends using flare nuts from the equipment manufacturer, not the line set manufacturer. He covers other flaring best practices as well. The charge is quite small in mini-splits, so weighing the charge and being careful and deliberate during charging is critical. Refrigerant leaks can also be highly problematic; corrosion and poor flare connections are common causes of leaks.  Craig and Bryan also discuss: Hyper-heat systems Coefficient of performance (COP) and BTU output Moving between PSC and ECM or inverter technologies Mini-splits vs. VRF/VRV technologies Pressure testing and leak detection Compressor diagnosis  Thermistors and electrical resistance Heat sinks and mounting circuit boards Selecting a location to install a mini-split Things to consider when checking the charge Why measure superheat and subcooling? Cleaning and maintenance best practices   Check out Craig’s YouTube channel at https://www.youtube.com/@acservicetech.  Starting January 1st, 2023, you can buy Craig’s book on his website, which has a bunch of other good resources. Visit that site at https://www.acservicetech.com/. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
50:05 1/3/23
CO Doesn't Leak w/ David Richardson
David Richardson from NCI returns to the podcast to talk about why CO (carbon monoxide) doesn't leak and what it does instead. CO is a highly dangerous gas that is colorless and odorless, and we can keep ourselves safe by staying aware of it with personal low-level CO monitors. However, CO doesn't leak; it spills, especially via backdrafting, a blocked flue, or updrafting. Whenever the flue gas comes back inside the structure unintentionally, there is room for a potential CO problem. With proper testing, we can determine the cause of that spillage and make the best choice to stop it from happening. When there is an excessive draft, there's often turbulence in the draft hoods, which leads to spillage. Spillage commonly happens at the draft hood, but it can also happen near the burner compartment of a gas appliance. Smoke tests won't detect that, but CO testing will. However, we need to look for rising CO levels over the run cycle of the equipment. If you test CO levels in the ducts, you're only seeing how the fans are distributing the CO; you're not checking the likely source of CO. Water heaters often give visual clues of improper venting, especially if there's soot, rust near the venting, or discoloration near the burner compartment. David and Bryan also cover: CO poisoning symptoms CO monitors vs. alarms The roles of stack effect and airflow in CO spillage Air taking the path of least resistance CO testing best practices CO and changes in sinus pressure Combustible gas leak detectors Low-level CO monitors Wind and its effects on pressurization or depressurization Electric appliances, generators, and CO poisoning   Learn more about NCI's training courses at http://nationalcomfortinstitute.com/. You can also contact David directly at davidr@ncihvac.com.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
38:30 12/29/22
One HSI Furnace Control to Rule Them All w/ Jim Fultz
Jim Fultz with Emerson White-Rodgers returns to the podcast to talk about one HSI furnace control to rule them all, the 50M56X-843 Universal Single Stage Integrated Furnace Control. The 50M56X does not come with wiring harnesses; the control comes with the plugs that the majority of manufacturers use, making it a versatile and user-friendly universal part. It also works with the White-Rodgers Connect app to help you configure the part with the burners. You can also do some basic configuration when it comes to the blower motor. With the 50M56X and Emerson White-Rodgers Connect app combination, you can quickly and accurately configure the control without wi-fi or a password.  An igniter is included in the box with the 50M56X; the igniter must match the control. The control also comes with a three-digit display that communicates the microamp current from the flame sensor, meaning you don’t need to use a meter on the flame sensor. So, you can carry less truck stock and complete more calls with this universal part. The device also has some potentially useful extra features. For example, the 50M56X stores error codes for 14 days, not permanently, to prevent causing confusion for future technicians. It also has a bus connector for the thermostat and a dehumidification terminal for thermostats with dehumidification capabilities. Jim and Bryan also cover: White-Rodgers universal vs. aftermarket vs. OEM parts Blower speed and X13, ECM, and PSC motors Near-field communication (NFC) capabilities  Cross-referencing Technology and ethical business 50M56X warranty information Integration with Sensi thermostats WR Mobile App (available on Google Play and the App Store)   Learn about Emerson White-Rodgers and their featured products on our partner page HERE. Check out the wide array of products and resources Emerson White-Rodgers has to offer at https://emerson.com/universalcontrols. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
39:16 12/27/22
Using Ice to Balance Energy Consumption
Yaron Ben Nun from Nostromo Energy joins the podcast to talk about ice banking, a way of using ice to balance energy consumption. Nostromo Energy is an Israel-based company that has recently started working in California. Water has a very high latent heat of fusion, meaning it can absorb and store a lot of energy between its solid and liquid states of matter. By storing ice, Nostromo Energy can support commercial and industrial structures that utilize chiller-type applications by offering a clean and sustainable battery thanks to water and its physical properties. Load balancing or management will be critical as the electrification of heating sources continues. Lithium-ion batteries aren't sustainable solutions in many of these cases, and that's where ice banking can support the grid by providing a thermal battery. Water offers many advantages as a medium for storing energy, especially since it is natural and doesn't have the numerous economic and labor concerns that come with the production of many other batteries. However, there have been some challenges with the widespread adoption of ice banking, especially when it comes to retrofitting and the ability to match the demand for new power stations. Water is also heavy, meaning that it can be difficult to manage in rooftop applications. Nostromo Energy keeps working to solve those problems and increase the coefficient of performance (COP), especially by maintaining a relatively high freezing temperature.  Yaron and Bryan also discuss:  Yaron's career and Nostromo Energy HVAC equipment and the electrical grid Economic and labor factors of lithium-ion battery production Discharge rates and glycol cycles COP and compression ratio Heat recovery chiller technology Carbon counting, kilowatt-hours, and carbon emission Thermal energy storage and tax rebate eligibility   Learn more at nostromo.energy. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
32:41 12/22/22
We need to Pay Better! - An Audio Manifesto
Eric Kaiser and Ty Branaman return to the podcast to talk about why we need to pay technicians and field workers better in the HVAC industry and how small and medium businesses can help current employees. When the pay for entry-level HVAC positions can't compete with fast-food, retail, or warehousing jobs, we can't expect people to flock to the industry, especially since so much skill is required. Overtime is also almost unavoidable in many places, and it's a problem that requires a more nuanced solution than getting more trucks on the road. The tricky part about paying more for overtime is that it's challenging to implement pricing structures that charge the end user proportionally. As prices for equipment, fuel, and living essentials go up, the company often has to eat those extra costs if they want to pay their technicians fairly. In some cases, HVAC businesses feel bad for the customer when the cost of everything increases, which could be doing a disservice to the techs who deserve higher wages for their work. HVAC companies can increase their value by setting themselves apart in their markets, such as by performing unique services that benefit customers; effort and skill are required, which can justify higher prices. We have to be realistic about what our competitors are selling and work towards selling comfort, not just parts or systems. Eric, Ty, and Bryan also discuss: Challenges with reducing overtime HVAC sales and higher pay rates Customers' willingness to pay Base pay and incentives How managers can take care of their employees Understanding employee motivation Using profits for personal luxury items vs. reinvesting in a business Knowing our numbers Understanding employee discussions about pay   If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
47:23 12/20/22
Refrigerant Myth Busting w/ Dr. Chuck
Dr. Chuck Allgood from Chemours returns to the podcast to do some refrigerant myth-busting. Many people don’t understand why high-GWP HFCs can impact the atmosphere if the refrigerant is heavier than air. High-GWP HFCs exist for a long time, and they last long enough for natural mixing and the wind to distribute their molecules throughout the atmosphere. HFOs, by comparison, are more reactive in the atmosphere and have relatively short lifespans, meaning they have less of an effect on the environment. Even though refrigerants with lower GWPs are entering the market, it’s always been our job to keep refrigerants inside the system where they can’t harm the environment. However, when leaks occur, these lower-GWP refrigerants break down quickly outside the system but not inside it. Contractors and manufacturers should still work together to reduce leak rates as much as possible, even as we keep innovating. Another common myth is around “natural refrigerants,” which are common in some forms of refrigeration, but “natural refrigerants” may be a misleading term; although you find them in nature, they undergo heavy manufacturing and processing before being used in HVAC/R systems. Even “non-toxic” and “non-flammable” labels for A1 refrigerants may be misleading, as they don’t capture the full picture of their risks. There are also some myths around oil miscibility; oil still needs the help of refrigerant velocity and volume to move it through a system. POE and PVE oil are great in terms of miscibility and also get entrained in the refrigerant to ensure good oil return to the compressor. Dr. Chuck and Bryan also discuss: Dr. Chuck’s recent work and research “Heat rises” and buoyancy Pseudoscience HFO stability and reactivity Trifluoroacetate (TFA), toxicity, “forever chemicals” Education and change in the industry “Future-proof” vs. innovation Phosgene   Learn more about Chemours and their A2L training at opteon.com. You can also check out the Chemours/Opteon YouTube channel at https://www.youtube.com/@OpteonProducts/videos.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
38:06 12/15/22
The Good, Bad and Ugly of Trade Schools
Ty Branaman and Eric Kaiser return to the podcast to discuss the good, the bad, and the ugly of trade schools. They cover the opportunities and challenges they've observed in trade schools. As with for-profit colleges, for-profit trade schools market programs aggressively and can take people who are at a crossroads in their life and saddle them with debt. In some cases, trade schools are hesitant to fail people and end up passing people who don't have the technical proficiency to be effective tradespeople. Sometimes, trade schools don't emphasize practical skills and contractors' experiences as much as they could, either.    The tricky part about trade schools is their allocation of resources, which instructors typically can't control. Sometimes, too much money is spent on equipment, and not enough is spent on the instructors. There needs to be an appropriate balance of both in an effective program. Administrative distractions can also make programs less likely to produce effective technicians. The admission process also doesn't always sort people into appropriate classes; many people with low proficiency are put into classes that are too advanced for them. People are going into trade schools with less mechanical aptitude than in previous generations, and trade schools often skip over the basics of tool use. Students need to know how to use tools before they learn how to fix systems, and that tool proficiency needs to be reinforced. Continuing education is also more focused on paperwork than application and isn't as thorough as it probably could be. Ty, Eric, and Bryan also discuss: First-generation trade school graduates Administrative challenges with trades instructors Motivating students Instructor qualifications "PowerPoint teaching" Automated systems Bringing work experience to the classroom Where does podcasting fit into trades education?   If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
45:56 12/13/22
Selecting Proper Cleaners w/ John Pastorello
John Pastorello from Refrigeration Technologies returns to the podcast to talk about selecting proper cleaners for various HVAC/R jobs. From the beginning, the goal of Refrigeration Technologies has been to make cleaners that are safe but have the same effectiveness as the strong, hazardous varieties in the industry. The more hazardous cleaners are not food safe and may be corrosive, dangerous to inhale, or irritating to the skin or eyes. Some cleaners can also damage components; brighteners aren’t recommended for use on aluminum coils for that reason.  John is a fan of foaming cleaners because the foam gives the cleaner more contact area and holds the detergent in place for a longer time. Foaming cleaners tend to be good for degreasing. However, if used improperly, the foam can overflow in the drain pan and get messy. Many residential and light commercial HVAC contractors may benefit from keeping Viper EVAP+ for evaporator coils, Heavy Duty for condenser coils, and Brite only when there is an extremely dirty condenser coil. The Viper aerosol coil cleaner can also work well for small systems. The Pan & Drain Treatment also keeps drain sludge and odors at bay inside condensate lines and pans.  Instead of relying on harsh chemicals to dissolve microbial growth, Refrigeration Technologies cleaners help use enzymes to dissolve odor-causing biological material in HVAC systems. John and Bryan also discuss: PPE to use when working with cleaners Acid-based cleaners and “non-acid” cleaners Dwell time and contact Dilution ratios NSF registration and what it means to be “food-safe” Viper Venom Packs   Watch our 3D video showing how to use several Refrigeration Technologies products HERE. Learn more about Refrigeration Technologies products and resources at refrigtech.com.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
39:08 12/8/22
Good Tech, Good Service Manager?
Eric Kaiser and Ty Branaman return to the podcast to talk about the progression from technician to service manager and if a good tech always makes a good service manager. They discuss career paths, differing skills between technicians and service managers, and how HVAC/R companies can support techs who wish to remain techs. In many cases, top technicians are pulled into service manager positions to keep them with the company. Sometimes, older technicians who have lost some mobility and strength over the years end up going to managerial positions to stay in the industry. Some people genuinely want to acquire managerial positions. Not everybody is motivated by promotions, and HVAC business managers would benefit from knowing what their employees value and want for their professional lives. Just as we have to teach technicians hard skills to be good at their jobs, we have to teach soft skills to service managers. We can't expect skilled technicians to enjoy or feel comfortable in leadership positions without knowledge of the expectations and required skills. When people genuinely want to go into service manager positions, they can benefit from having a clear path supported by goals and frequent performance reviews to keep them on the right track. However, some people may want to stay technicians; we can do right by them to keep their bodies in good shape so that they can get the most out of their careers and be able to enjoy all types of activities after they retire. Ty, Eric, and Bryan also discuss: Leadership training Setting expectations for positions Keeping technicians happy Residential vs. Commercial HVAC soft skills Taking care of employees over customers Making room for different personalities and providing opportunities for them   If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
34:09 12/6/22
Why Aren't the Trades More Respected? w/ Kimberly Llewellyn
Kimberly Llewellyn from METUS joins the podcast to talk about the value system around the trades and why the trades aren’t more respected. In many cases, the people who are involved in engineering and design miss the practical details that the tradespeople would be able to pick up on. In many cases, tradespeople aren’t consulted early enough in the design process, and their input deserves to be brought to the table. Often, not everyone on a project team is on board with the project's goal, and the trades need to be on board from the beginning to work towards the same goal as the architects and engineers. However, the trades aren’t as respected because of the current American dream’s emphasis on 4-year college, even despite the student loan debt problem many college graduates have. Despite that, building and troubleshooting systems that are necessary for survival is a fundamental skill for society. The trades can be especially hard on people and leave them feeling beaten down. To reengage the tradespeople and affirm their value, we need to give them credit for their contributions and expertise. It would also benefit younger generations if we could map out a trades career path and make the career progression opportunities clearer. Kimberly and Bryan also discuss: Kimberly’s experiences with the trades Theory vs. practice 4-year college, the trades, and our current value system in education Professionalism and being treated as professionals Revising contracts and liability concerns (for contractors/subcontractors) Having mutual respect Consultation and what it means in the trades Working for manufacturers and other career opportunities Contracting as a “race to the bottom” Funding training programs vs. investing in people Mentorship in the trades Underpriced bids and pricing methods   If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
91:28 12/1/22
Getting More People Into The Trade
Eric Kaiser and Ty Branaman return to the podcast to talk about getting more people into the trade. They focus on how the HVAC/R industry could be better at attracting and training skilled workers, not just getting more bodies to fill HVAC/R tech and installer positions.  People are starting to see more value in skilled trades careers, but it's difficult to find people who share your company's values and want to grow as HVAC/R professionals. Skilled tradespeople need time, education, and money invested in them, so it can be difficult for HVAC/R business owners to make those investments when other jobs pay close to the same without the same degree of investment from the company and the employee.  To attract more people to the trade, HVAC/R business owners ought to focus on how to give their employees a means of giving a good life. That means making incremental changes to employee pay, benefits, and training to make the trades a competitive option for people who want to improve their skills and grow. We could consider increasing entry-level pay to attract skilled people, allowing us to be more selective in our hiring. Performance reviews can also be more goal-focused to help HVAC/R talent grow within a company. Companies also ought to focus on training their tradespeople to use the many tools at their disposal nowadays; providing these tools and acknowledging the needs of employees will make the industry much more appealing and competitive. Eric, Ty, and Bryan also discuss: Labor organizations Making gradual changes to the industry Competing with other similar industries Changing landscape of job ads and applications "Back in my day..." Ways of providing tools   If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
24:28 11/29/22
Becoming a Complete Tech
Genry Garcia returns to the HVAC School podcast to talk about what becoming a complete tech really means and entails. He talks about his professional journey and what we must do to address our deficiencies. Career progression looks a bit different for everyone, with some technicians going to trade school and others starting as helpers and working their way up. We get used to taking readings and start noticing patterns. Then, we start understanding why we see certain pressures. Our experiences are our most valuable tools for becoming better technicians, but they can be reinforced with other learning materials, including books and podcasts. There comes a point when we acknowledge that we are solid technician but may want to specialize in a certain aspect of the trade. For Genry, that was building performance and humidity control; along the way, he listened to people who knew more than him and took on many jobs that he’d learn from and would keep him humble. Everything goes back to the basics; we have to be able to solve all the basic problems and understand the fundamentals. Then and only then can we start thinking about building performance and focus on becoming experts at it. However, we also have to assess our ecosystem and see if it would allow us to grow or if it’s more suited for stability. We also have to be willing to be wrong and grow from those mistakes. Genry and Bryan also discuss: The pros and cons of trade school Egos and admitting wrongdoing Mental models Humidity control Looking back on previous work with shame Building envelopes, pressures, and leakage Where and how to learn more about building science and performance Self-auditing and the Dunning-Kruger effect   Get in touch with Genry on Facebook by joining his Facebook Group HERE. If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
40:24 11/24/22
Inductive Current Myths - Short #158
In this short podcast in our electrical myths series, Bryan talks about some inductive current myths. There is a common myth surrounding voltage drop in inductive loads. When you decrease the voltage in a circuit with a resistive load, you'll see a relatively proportional drop in resistance (ohms) and current in accordance with Ohm's law. So, we'll see a decrease in current, but we have to keep in mind that load temperatures also affect the resistance (and the current, by extension). Some people will claim that reducing the voltage in an inductive load (like a motor or compressor) will increase the current. That is actually generally a myth; many people believe this myth because the current drop is NOT proportional, unlike in resistive loads. The resistance that shows up in a motor is called inductive reactance, which is an opposing magnetic field that creates back electromotive force (back EMF) and impedes the circuit. Back EMF and inductive reactance contribute to the impedance or total resistance of the circuit. Decreasing the voltage may cause the resistance to increase, as some of the work will start contributing to heat instead of mechanical motion; the motor derates, becomes less efficient, and draws more current than it needs, but it doesn't actually draw more total current. However, some variable-speed motors on VFDs may draw more current because the motor module speeds up the motor to make up for the voltage deficiency, static pressure, etc. ECMs also fall into this category and may draw more current if the motor module or VFD calls for it. However, in terms of simple electrical math without VFD logic, the current won't typically increase if the voltage drops, even in inductive loads.   If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
09:14 11/22/22
Why it REALLY gets hot upstairs w/ Alex Meaney
Alex Meaney returns to the podcast to explain why it REALLY gets hot upstairs and what we can do about it. He also talks a bit about his new business. Heat technically doesn’t rise; warm air is less dense than cooler air, so cooler air sinks as warmer air rises. In many cases, people blame stratification and the stack effect for warm upstairs areas, but there may actually be other issues at play, especially if the issue only seems to happen in the summer.  Many apparent convective problems are actually due to building science errors, especially poor insulation when walls are exposed to attic space. When air moves via convection, it brings the heat it contains with it, which can contribute to comfort problems. To help figure out what is going on, try to see what the floor temperature is; a cold floor usually indicates a building design mistake, particularly a joist bag problem.  Some of the solutions that may sound good aren’t actually that effective, including placing return ducts higher. In many cases, we have to think about fixing the actual building, not the HVAC system. Some attics that are poorly ventilated and insulated will need to be reinforced. Alex and Bryan also discuss: Mean HVAC Consulting & Design Wind washing and exposure within the insulation R-value Pressurization and how it relates to hot air “rising” Manual J and its shortcomings with significant heat gains/losses Duct design and using a Ductulator Soffit vents, ridge vents, blown-in insulation, and infiltration Why building science skills are important for HVAC technicians Poorly conceived home designs Diagnostic tips and tricks Vapor-permeable air barriers Sizing, capacity, and power consumption   Learn more about what Alex is doing at meanhvac.com.  If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
49:55 11/17/22
Electrical Myths - Single phase is Really 2-Phase - Short #157
In this short podcast, Bryan busts the common electrical myth that single-phase 240v power is really two-phase power. When power goes into a structure that runs 240v appliances, we may understand that two 120v sine waves are 180 degrees out of phase with each other, but that isn’t 100% accurate. If we were to use an oscilloscope to watch the electrical sine waves, we would see two sine waves 180 degrees out of phase because the transformers are center-tapped. Center-tapping creates a neutral center point that becomes our reference. The transformer has two sides: a primary and a secondary. The number of wraps on each side is proportional to the other, and the number of wraps also dictates whether a transformer steps the voltage up or down. However, when you use the center tap as a reference, that also makes the voltage appear to be halved.  In many residential structures, a single phase of power goes into the transformer from the power company. If you were to use the center tap as your reference on each side of that transformer, you would read 120v; the two 120v readings add up to 240v. However, if you were to use the other side as the reference (as in a corner-tapped transformer), you would read 240v.  On an oscilloscope, you would see the same thing; using the center tap as the reference, you would see two 120v sine waves completely opposite each other. If you were to measure completely across the transformer, however, you would see a single 240v wave, which is larger.  Remember: only one phase comes from the power company. We only appear to get two separate waves because of our available point of reference.   If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Check out our handy calculators HERE.
09:06 11/15/22